Comsol+Matlab on Linux cluster: "No user name and password could be obtained"

A problem I had and its solution, for the record. (Just seeing as nobody reported these error messages yet.)


Just tried running Comsol+Matlab on a cluster, using what seemed to work before:

$ \comsol server -tmpdir $TMPDIR < /dev/null > test2016apr01.log &

But Matlab said: "No user name and password could be obtained" after I entered "mphstart()".

So it turned out that Comsol server collapsed, and the log file said:



The way around this that I found was to first run Comsol server as follows:

$ \comsol mphserver -tmpdir $TMPDIR

It will then ask for a username and password. Luckily, it remembers these for the next time it runs, because it's not possible to connect to the above (at least with the way our cluster is set up, and probably others). So, shutting it down and running as follows, now works:

$ \comsol server -tmpdir $TMPDIR < /dev/null > test2016apr01.log &

$ matlab

Now, the right directory needs to be added to Matlab's PATH. For me this is /usr/local/comsol/5.1/mli but for others it's likely to be different. There is probably a way to permanently store this somehow, but I haven't found it yet. Post if you have a way (this is on Linux; it's easy on Windows).

Now this works:

>> mphstart()